In a 5G system, a User Equipment (UE) in an idle state needs to monitor a Physical Downlink Control Channel (PDCCH) and blindly detect the PDCCH in a common search space to acquire Downlink Control Information (DCI) therein, so as to receive common control messages, such as Remaining Minimum System Information (RMSI) or paging messages, in a Physical Downlink Shared Channel (PDSCH) indicated by the DCI. Time-frequency resources corresponding to the PDCCH to be monitored by the UE in the idle state are referred to as a Control Resource Set (CORESET).
A base station sends a Master Information Block (MIB) in a Physical Broadcast Channel (PBCH) to indicate a first CORESET the UE needs to monitor in the idle state, so that the UE blindly detects a PDCCH in the first CORESET to acquire information such as RMSI when in the idle state. Further, the RMSI further indicates a second CORESET to be monitored by the UE in the idle state, so that the UE may blindly detect a PDCCH in the second CORESET in the idle state to acquire paging messages or the like. The first CORESET and the second CORESET are collectively referred to as an idle CORESET.
In specific product implementation, a base station at a network deploys the idle CORESET based on an application scenario, and sends the idle CORESET to a UE through signaling, so that the UE monitors a PDCCH on the configured idle CORESET after searching cells. Currently, the idle CORESET is directly indicated by signaling. When the signaling indicating the idle CORESET is large, signaling overhead of the network is large accordingly.